This invention generally relates to a method and apparatus for translating a longitudinally applied brake input force from an air chamber into a laterally applied brake input force to bring brake pads into braking engagement with a rotating disc.
The operation of air disc brake assemblies is well known. A disc is mounted to a rotating wheel component for rotation about a lateral axis and a caliper is mounted to a non-rotating vehicle component. The caliper supports and positions a pair of brake pads on opposing sides of the disc. An actuating mechanism brings the brake pads into engagement with the disc in response to a braking input command. The actuating mechanism includes an air chamber that applies the force to bring the pads into contact with the disc.
Traditionally, brake manufacturers provide air chambers that can be installed in either an axial position or a radial position. The axial positions extend in a direction generally parallel to the lateral axis and the radial positions extend in a direction radially outward from the lateral axis. These positions make packaging on certain types of vehicles, especially low floor buses, very difficult and can result in intrusion to the bus aisle width.
In an attempt to address packaging difficulties, brake manufacturers have also provided brake chamber tangential mounting configurations at increased cost and complexity. Further, this installment position typically requires the air chamber to be positioned close to the wheel, which is not desirable for all vehicle applications.
Additionally, axle manufacturers are often required to package the air chamber into various different installment positions to meet varying OEM specifications. Thus, one axle assembly could have several different air disc brake assemblies installed in multiple different positions. This requires significant engineering time to re-package and design mounting interfaces for the air disc brake assembly and may even require modification of the axle assembly itself, which significantly increases cost and part proliferation.
Thus, it is desirable to provide an air disc brake assembly that can be mounted in a plane parallel to a wheel while still generating an axial input braking force and which can be easily installed in a variety of installment positions as well as overcoming the other above mentioned deficiencies with the prior art.
A vehicle brake assembly includes a disc that rotates about a lateral axis and a pair of brake pads that are positioned on opposing sides of the disc. The brake pads are supported by a caliper that is mounted to a non-rotating vehicle component. A first actuator applies a force in a first direction parallel to the lateral axis to bring the brake pads into engagement with the disc during a braking operation. A second actuator generates a force in a second direction transverse to the lateral axis in response to a brake input command. An adapter is used to convert the force applied in the second direction into a force applied in the first direction.
In a disclosed embodiment, the rotating disc rotates within a first plane and an air chamber is mounted in a second plane that is spaced apart from and parallel to the first plane. The air chamber is responsive to brake input commands operates the second actuator.
Also, the adapter allows the air chamber to be mountable in a plurality of installment positions. The installment positions preferably extend out radially from the lateral axis and include at least one tangential installment position with the air chamber extending tangentially relative to the disc.
In the preferred embodiment, the adapter includes a lever having one portion connected to the first actuator and another end connected to the second actuator. The lever is pivotally supported on a pin. An adapter housing is mounted to the caliper with the lever being substantially enclosed within the housing.
The subject invention provides a brake assembly that can be easily packaged in multiple different mounting configurations without requiring significant redesign of an axle. Further, the subject invention provides a simplified method and apparatus for converting a longitudinally applied brake force into a laterally applied brake input force to allow an air chamber to be mounted parallel to a wheel. These and other features of the present invention can be best understood from the following specifications and drawings, the following of which is a brief description.